The D3F3ND3r is an EV3 controlled cannon with automatic loading and firing capabilities. It can be fully remotely controlled or operate automatically. The clip holds 12 shots and the gun delivers about 2 rounds per second. The fighting range is limited by the Ultrasonic Sensor with a maximum detection distance of 255 cm. The maximum shooting distance is 4 m with the muzzle velocity of 6.2 m is exceeding the detection range of the detector. The D3F3ND3r has full automatic surveillance capabilities and patrols the predefined area automatically. Target identification, distance measurement and angle adjustment is autonomously performed. The full alignment of the gun is then acoustically indicated. For activation of the gun, a confirmation my means of an infrared control unit is required. It still has problems with following fast targets and when fighting multiple targets it gets easily confused.